The invention concerns a process for the production of a profile structure from dry powder material based on the precharacterizing clause of claim 1, along with an apparatus for carrying out the process.
Isostatic or quasi-isostatic presses for producing solid or hollow structures or profiles, for example tubes, have become known from British Pat. No. 2,074,086; U.S. Pat. No. 4,370,120; and U.S. Pat. No. 3,193,900 and consist essentially of a mold cavity that is surrounded and limited by a flexible form. The flexible form is capable of being acted upon, in its axial length and radially from all sides, with a pressure, for example hydraulic or pneumatic, whereby the powder material capable of being brought into the mold cavity, for example via a pressure space, can be compacted and pressed in the radial direction. However, it is possible, through means of these previously known presses and the therewith associated production processes, to produce only profiled pieces, hence, for example, tubes which are limited in their length.
However, having become known from German Pat. No. 752,704 and German Auslegeschrift No. 21 47 333 is also a process and an apparatus for the step-by-step production of a continuous extrusion of pressed pieces. In the case of the previously known extrusion process from German Pat. No. 752,704, however, compacting is done step-by-step, from top to bottom, only in the axial direction by means of a press ram. This can, on the one hand, work out disadvantageously for a uniform compaction and on the other hand, for sufficient binding of those extruded sections compacted step-by-step one after the other.